TiKL, located in Sunnyvale, CA, is the creator of Touch to Talk, a mobile communications application that brings walkie-talkie functionality to iOS and Android devices. With Touch to Talk, customers can make real-time, push-to-talk calls with one person or a group of people at the same time, regardless of distance. TiKl’s customer base is divided evenly between domestic and international users, who range in age from teens to early thirties. TiKL released Touch to Talk in 2010 and estimates that the application has been downloaded 28 million times since its launch. According to App Annie analytics, Touch to Talk ranked #1 on Google Play for several months in 2010 and 2011.

TiKL’s founders leveraged their telecommunications background to develop a product that replicates cellular push talk on smart phones. According to TiKL, using Amazon Web Services, (AWS) made it easy for the start-up to launch Touch to Talk. “We considered other cloud providers, but from our experience, we knew that we were building our product on a strong foundation with AWS,” says Nan Zhong, co-founder and CTO.

The Touch to Talk application was successful beyond their expectations. “We weren’t sure how many users would sign up,” says Zhong. “We reached 1 million users within the first 2 1/2 months—solely by user word-of-mouth—and the business has grown non-stop. We had to scramble to handle demand.” In the beginning, TiKL experienced scaling issues because of the way they designed the application. “AWS gives us the right building blocks, but it’s up to us to design correctly and build the system in a correct way,” says Zhong.

In 2010, TiKL redesigned Touch to Talk’s back-end infrastructure to take advantage of the elasticity and scale of the AWS Cloud, enabling TiKL to grow to 20 million customers in less than 2 years. Zhong says, “The agility on the server side was a game changer for us. The system is architected to scale horizontally. We could add capacity by simply provisioning new Amazon EC2 instances in seconds.” Touch to Talk runs on a Java stack and Linux on Amazon Elastic Compute Cloud (Amazon EC2) with AWS Elastic Beanstalk as the front-end of the internal web service. Amazon CloudWatch provides monitoring. Behind the scenes, TiKL was still doing a lot of manual work to optimize the relational database service, (a combination of SQL and Amazon SimpleDB), to handle users on a massive scale.

Zhong and his partner were spending several days each quarter optimizing their SQL database. When Amazon DynamoDB became available, the team built new storage-dependent infrastructure components on DynamoDB to take advantage of the highly scalable database service. “Before we moved to DynamoDB, we had to manually figure out database limits and how the storage layer of the system would scale,” says Zhong. “DynamoDB performs these tasks automatically and scales horizontally by design. With DynamoDB, we have time back to build features that are visible to our customers and make the application more useful and helpful.”

By 2012, TiKL was accepted into Y Combinator’s startup accelerator program. Y Combinator helps launch start-ups by offering seed money, advice, and networking connections. Participating in the program gave TiKL a chance to meet other start-ups and compare solutions. “We talked with start-ups who had the pain of migrating legacy stacks. We don’t have that baggage. We started out on AWS and we’re staying that way. Without making any changes, we’re likely to see a 20 to 30 percent cost reduction, year-over-year, just by staying on the AWS platform. That savings gives us the freedom to take advantage of the AWS model and pass savings on to our customers.”

Because of the accelerator program, TiKL received additional investment funding from General Catalyst, Lerer Ventures and SV Angel. TiKL used the funding to hire three additional engineers to develop Talkray, a free calling and messaging application for Android and IOS devices. “By using DynamoDB, we saved as least two months developing Talkray because it simplified the amount of time that we to spend managing, designing, and operating the system, says Zhong. App Annie ranked Talkray #1 across all Apple Store categories in 7 countries, and TiKL estimates that the application has millions of users. “After we were featured by Google Play, the number of downloads for Talkray expanded exponentially,” say Zhong. “We used DynamoDB to scale and add capacity seamlessly.” Overall, TiKL is able to support over 30 million customers across both applications on the AWS Cloud with less than half a full-time engineer working on the infrastructure.

TiKL credits Amazon EC2 Reserved Instances for helping the company continue to reduce costs. “The business innovation that AWS has brought to the market is tremendously helpful to us,” says Zhong. “We’re estimating saving between 30 and 40 percent using Reserved Instances.”

“AWS is an enabler of a whole new breed of start-ups, including us,” says Zhong. “We’re looking forward to continuing to innovate on the AWS Cloud.”